Improvement in mortising-machines



JOHN R'IOH'ARDS, OF CINCINNATI, OHIO.

yLettera .PatentQN-o. 81,407, dated August 25, 1868.

IMPROVEMENT IN MORTISING-MAGHINES.

@te .tlnbale :riant it in tigen Enters atent mit linking part ut tigt smite.

TO "WHOM, IT MAY CONCERN:

Be it known that I, JOHN RICHARDS, of Cincinnati, in the `county of Hamilton, and Staterof Ohio, have made ccr'tainlmprovements in Powcr-Mortising Machines; and I hereby declare the following to be a. full and exact description of the same, reference being had rto the accompanying drawings, forming a part of this speciL Figure 3 is afront elevation of a machine complete, with my improvements on.

cFigure 2 is a side elevation of fig. 3. i

Figure 1 is a 'vertical section through the ram a, tig. 3, on line s's.

4 Similar letters of reference, on the different figures, indicate corresponding parts.

The nature of this invention consistsm First, in a reverse-threaded screw, for projecting the chiselbar down upon the work. 4 Secondly, in gearing and devices foroperating this screw, by means of a frictional clutch, using the for-ce of the driving-power to operate the same; and

In a graduated weight, to return thechisei-bar after the mortisc is completed, the graduated resistance of ,l

thc weight enabling the operatorio stdpthc chisel at any point of its downward stroke.

Also, in a.reversethreaded screw, for adjusting the table to receive work of different-depths, andto receive the forceof the chiselbar directly, and communicate it to the foundation on which the machine stands. In power-mortising machines, vas hitherto constructed, thechisel-bar is thrown into motion, or brought down to the wood to bemortised, by the Iveightof the operator upon a treadle; or the wood, with the table, has been raised in the same manner. In either of these cases, the long movement ofthe treadle, together with the great weight required, has made the operation laborious to the operator, particularly in machines constructed for a heavy class of work; neither has the chisel-bar had a positive movement, but reacted upon 4the treadle.

To ohviate these objections, and to. secure a positive movement of the reciprocating parts and chisel-bar, is

the object ofthe invention illustrated.V p

T o'enahle others skilled in the art to make andtusc my invention, I will proceed to describe the mode of constructing and manner of operating the same, with the aid of the drawings. i

A is the main column or support, coredout hollow, and mounted on a broad base, B, in the usual manner.

C is the crank-wheel or eccentric, and el the drivingshaft. E is a linker connection between thc crankwheel C and thereciprocatng rain a.

b is a frame, bolted to the front of the column A, arranged with guides to receive the ram or carrier a, and also an extension, to receive the lower bearing of the chisel-bar g. l

I is. the chisel-bar, bored out at the lower end to receive the chisel i, the upper endIbeing-tted into the nut Za j vThe right-audlci`t throadedscrew m is tapped into and through the nut K, alsoA with a reverse thread into the nut Z,at the bottom, as shown in iig. 1,'and by red lincs, iig. 2.

n and fn, are bevelsgears for rotating the screw m, upd `are operated` bythe shaft p. "q is a belt, passing from the`pnlley'1' to a driving-pulley on shaft d, as shown in tig. 2. o is a friction'al clutch or plate, movingon a feather in thc shaft p, with its face iii' contact, or nearly. so, with the side of the pulley 1f, iig. 2.. fOn` this {lang-e o is formed a hub orextension, s, on which iswtound the belt t, for raising the weight, shown hy dotted lines at u., iig. 2. 'v isa bell-crank, communicating with the treadle t0, and is used to force the plate o up against the pulley 9'. :e is` the driving-pulley,.and ythc table for supporting the timber to he mortised. The table y is not different from the ordinary table u sed on this class oi' machines, is moved by rack and pinion and handwheel z. It has a compound'movcment with and transverse to the linie of the-Inortse, but the manner of supporting is diilercnt from that commonly adopted. The table y, with the supporting-bracket M, rests upon a large screw,lW, which is placedccntrally under the chisel-bar fand the force of the blow is thereby Communicated to thc foundation `at F, relieving the guidesff of theiforce. This screw is threaded, like the screw m', with reverse or rightand-left threads, tapped into the nut H, and throng-h the base at F.

The hand-wheel k is to elevate or depress the table, by rotating the screw W, moving the table a distance equal to twice the pitch vof the screw, at each revolution. i

Tn operating vthe machine, the ram or carrier a, with the screw m and chisel-bar h, has a reciprocating motion equal to the stroke of the eccentric, C, the screw m moving freely through the bevel-gear n, but pre- 'vented from turning by a feather, shown by dotted lines at o o', lig. 1. The gear n has a fixed bearing, s', formed on the frame as shown by red lines, fig. 2.

To project the chisel-bar L down, and cause the chisel z' to enter the wood, theoperator presses with his foot upon the treadlc w. This, by means of the bell-crank v, fig. 2, forces the plate o up against the face of the pulley 1'. This pulley being continually in motion, by means of belt q rotates thefiange o, and with it the shaftp and bevel-gears n n, with the screw 1n. This projects the nut l and chisel-bar i downward a distance equal to double the pitch of the screw, at each revolution, the screw m moving down out of the iixled nut k, one thread at each turn, and the nut l receding from the screw in the same manner.

The nut l being fixed to the chisel-bar L, prevents it from turning.

The pulley 7 runs loose on shaft p, and bears on its reverse face `against the hub c on the bracket u', tig. 2. The shaft p ,and clutch-plate o, in rotating, wind up the large weight W, by means ofthe belt t. Thisbelt, by winding in the form of `a spiral on the hub of o, offers a graduated resistance to the rotation of shaft p, enabling the operator to stop the movement of the screw m at any point.

When the foot of the operator is removed from the treadle w, the weight u rotates the shaft p in a reverse direction', and returns the chisel-bar h and screw m to the position shown in fig. 1, when the chisel-bar is in its disengaged or highest position.'

The graduated resistance of the weight u, by the spiral winding of the belt t, meets precisely the conditions of reversing the screw m, commencing with an increased power and diminishing as the chisel returns fo its upward position. This feature is also an essential element in the use of the driving-power, to throw the chisel into motion or into the work, as without this the* action would bc positive, and the operatorv unable to work the chisel down gradually, to suit the conditionsof the work, and the kind and depth of the mortises to be formed.

Having thus described the mode of constructing, and the manner of operating my machine, what I regard as new, and desire to -secure by Letters Patent, is-

1. The right-and-left threaded screw m, and fixed and movable nuts and l, when used to operate the chisel-bar of a mortising-maehine, as herein set forth and described.

2. The shaft p and bevel-gears n and 1t, when used in combination with the ram or earrier a, and as a means of rotating the reverse-threaded screw m, substantially as specified and shown.

3..The shaftp and bevel-gears n and n, for rotating the screw m, as specified-and shown.

4. The beit g and pulley a', when used in combination with the ram or carrier a, and as a means of operating the reverse-threaded screw m, for feeding the chisel-bar down, substantially as set-forth and shown.

5. The friction-clutch, consisting of the plate o, pulley r, in combination withthe reverse-threaded screw m and carrier a, for -producing aggraduated feed ofthe chisel-bar 7L, for the purposes and in the manner shown.

6. The weight u and belt t, when arrangedto operate as a graduated resistance to the rotation of the screw' m, and as a means of returning the chisel-bar to its up stroke, arranged and operating as herein described.

T. The screw W, when formed with a compound or right-and-left hand thread, and used` as'ameans of adjusting the table-bracket M, arranged and operating as set forth and specified.

' JOI-1N RICHARDS. Witnesses:

W. S. KELLEY, W. E. LONDON. 

